Polysaccharides of soy-beans. Part III. Extraction and fractionation of polysaccharides from cotyledon meal

Abstract

Extraction of defatted soy-bean cotyledon meal, after prior removal of soluble sugars and protein, with ethylene-diaminetetra-acetic acid disodium salt furnished a mixture of an arabinogalactan and an acidic polysaccharide complex. The arabinogalactan has been shown to contain chains of 1 → 4 linked β-D-galactopyranose residues in which every fourth or fifth residue carries through C-3 a side-chain containing, on the average, two L-arabinofuranose residues joined by a 1 → 5 linkage. The acidic polysaccharide complex has been shown to possess a highly branched structure with residues of galacturonic acid, galactose, arabinose, xylose, fucose, and rhamnose in which side-chains are terminated by galactopyranose, fucopyranose, xylopyranose, and arabino-furanose residues.